Fakes and Garbage – Debutant Level Learning
In no particular order comes the following list of entry levels “Doh!” that we all have to pass through to learn the art of coin grading and identification. As I pass on to more sophisticated levels of doctoring, I thought it worth jotting down the basics as time permits. I’ll share each update on FB as they are added.
Purple Pennies
I have to wonder if Kath and Mark decided to call their shop for this reason, but purple pennies was one of my first bugbears on the path of coin collecting. After I had sent a coin to PCGS – which confirmed the coin as being cleaned – I sent an email to the Ebay seller in Tasmania explaining that his product was not a delightful toning, but tampered product. One year later he was still selling the same garbage with the same selling pitch. That’s one reason I’ve given Ebay the flick. Thus the first lesson in coin collecting is to be suspicious of colours that are too far removed from the norm, especially on bronze. Subtle pinks on the half penny on the left; strong purple on right. “Delightful Toning” LOL. Probably Brasso or something similar.
Environmental Damage – Conservation
Not as vulgar as a purple penny and not done with intent. Nonetheless, a poorly stored coin subjected to humidity – or as in the case of the camouflaged obverse below, a chemical reaction – will suffer similar disfigurement as the dumb doctoring witnessed above. I’ve been informed that this coin suffers from Dansco fever, as coins kept in the old Dansco albums were subjected to chemical leaching. Modern Mylar flips are the non-reactive solution to this storage conundrum. As a resident of tropical Darwin, I have the office aircon on 24 degrees almost 24/7. The patination of copper would be fierce in such humidity. I sent this coin to PCGS for them to explain what was wrong.
Environmental Damage – Grease and Oil
I was surprised to hear someone telling me they were using WD40 to conserve coins. The ingredients of WD40 can be found by clicking on this link. I’m quite confident that I would not want this product on a coin I’ve purchased. The long-term consequences are unknown. Prior to WD40 (1958), other collectors used various petro-chemicals to conserve their bronze. The image located in the selection of featured images above (Cert. #41446508) shows the long term consequences of one such intervention. In strong white light the coin is not quite as dark. Alas, an important variety of 1931 Melbourne has been destroyed by someone’s “thoughtful” efforts.
I use a biodegradable preserving oil in spray format on occasions where I’ve had to intervene to reverse damage to a coin. Typically this is following a solvent clean of PVC residue. I committed this process to a collection of attractive VF to UNC coins yesterday. They’ve been tucked away in a corner of the office for some years. I had thought the collection useless until I learned how to halt PVC damage before it became irreversible I’ve been pleasantly surprised by the results. After an overnight hold in tissue paper to absorb excess oil, I noted one coin was still shimmering with an oily surface. It’s the coin below, which has also witnessed environmental damage from someone’s efforts to conserve with petro-chemicals. The product is acting as a barrier and not permitting the ready absorbtion of my application. It is also a dark colour that PCGS will label Environmental Damage.
Environmental Damage – Excessive Corrosion
I loved this coin when I saw it for sale. It has a gorgeous patina. This coin came from Europe; apparently Europeans were big collectors of tokens back in the 19th Century. Alas, if you know old European houses then it’s of little surprise that this bronze mix succumbed to corrosion over the past century or more. It’s of note that PCGS will not give this coin a numerical grade. For this reason I’ve added this issue to the list of Fakes and Garbage – Debutant Level Learning. However, beauty is in the eye of the beholder and a collector may ignore the technical issue in favour of the attractive colour. I will remove this token from its holder and test the metal content with the XRF scanner – I’m nothing if not curious.
PVC – Polyvinyl Chloride
To make plastic flexible, some really nasty chemicals are added. Given the Darwin heat and humidity, I’ve seen some really ugly stuff come to my stall for sale. Click on the image below and look at the top left hand coin. That dusting on the coin is a chemical reaction that will eat into the coin and kill it. There are other means of identifying PVC and I will include them with further images.
PVC – The Green Gunk on Silver
PVC manifests itself on silver as a dusty white powder (which I’ve repeatedly mistaken for patina) similar to the image of the bronze coins above. Unlike bronze, which suffers oxidation in the form of verdigris (green gunk), green gunk on silver generally means PVC. There is a copper component in post-war Australian silver. If the alloys are incorrectly mixed, verdigris is conceivable. But 99.9% of the time, green on silver = PVC. See the two error coins below. Great mint error action going on with these two. The Sixpence looks like an alloy mixing error issue, while the working die is split in two and disintegrating on the shilling. Click on the image for a closer look at the PVC damage.
Similar reading: https://topendcoins.com.au/2021/08/21/so-ebay-ripped-you-off-what-are-you-going-to-do-about-it/
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